Baros Marine Centre

Scroll down

Marine Life Facts

Baros' Marine Biologist answers some of the most commonly asked questions about the underwater world.

Will a shark drown if it stops moving?

That depends on the shark. Generally, they have to swim for two reasons. First, sharks lack the swim bladder that most fish use to adjust their buoyancy – swimming creates lift that prevents sharks from sinking.

Second, sharks, like other marine animals, get their oxygen from the water. Bony fishes use muscles to pump water through their gills, where oxygen is extracted. Sharks, however, use a ramjet ventilation system that requires them to swim to force water to the gills.

However, sharks like nurse sharks have mechanisms to move water through their gills so they do not need to swim constantly to breathe. This method is called buccal pumping, whereby cheek muscles pull water into the mouth and over the gills.

How long can turtles stay underwater without breathing?

When they are active, sea turtles must swim to the surface to breathe every 30 minutes. When they are resting, they can remain underwater for as long as three hours without breathing.

Why do underwater photos look so blue?

The ocean looks blue because water – even when very clear – absorbs and filters out the red side of the colour spectrum so pictures look blue, unless you get close. For good underwater photographs, get as close to your subject as possible. Try to shoot up or across, in order to make your subject stand out from the background as much as possible.

Are the sharks at Baros dangerous?

No, our sharks are reef sharks, which do not attack humans. They have plenty of fish in the ocean to feed on. An unprovoked shark attack has never been recorded in the Maldives.

Is it true that the sea level is rising?

Yes. Over the past 100 years, the sea level has risen 10-25cm and scientists expect this to increase. Sea levels will continue rising even if the climate stabilises because the ocean reacts slowly to changes.

Why isn’t it permitted to take dead shells back home?

Empty shells offer shelter for hermit crabs and therefore must not be removed from our beaches. Hermit crabs use shells to protect their soft abdomen and have to find a new shell every time they outgrow their old 'house'.